Problem: Omar has walked his dog for a total of $40$ miles since he started walking daily. He has been walking $4$ miles each day. For how many days has Omar been walking?
Answer: The number of days that Omar has been walking is the total number of miles walked divided by the number of miles walked each day. $40\text{ miles} \div 4\text{ miles per day} = \text{number of days walking}$ $40\text{ miles} \div 4\text{ miles per day} = 10\text{ days}$